The chief medical officer has declared a third-degree heat alert from early Wednesday until Saturday midnight. The heat alert comes with advice to drink plenty, avoid the sun in midday hours and to stay in the shade, the national public health centre (NNGYK) and the disaster management authority OKF said in a statement. During heat alerts, people should use skin protection, stay in air-conditioned places when possible and avoid physical exertion during the hottest hours of the day, the statement said, warning of the dangers to the elderly, children and those with cardiovascular diseases in particular.